iCloud will not match up across devices

So if I have understood, for now you have not access to Finder/iCloud Drive ?

If you have access to your iCloud Drive folder, go to settings, iCloud and select the services you need to use (you can also clic on iCloud Drive "Options..." to select others Services/Apps.

if have not access to your iCloud Drive,

This is unverified but some users report it can work to resolve iCloud connection issues in Mac OS. Be sure you backup your Mac before attempting this procedure:

1. From the Finder, choose the “Go” menu and select “Go To Folder” and then enter the following path: ~/Library/Application Support/iCloud/Accounts/
2. Copy the files found in this location to the desktop or elsewhere that can be easily recovered if desired
3. Remove the files from the ~/Library/Application Support/iCloud/Accounts/ folder so that it is empty
4. Reboot the Mac

You will likely need to re-login to iCloud when the Mac reboots. You can also log out and back into iCloud if things are still not functioning correctly to regenerate new Account data files.

Or it could be the keychain the fault.

Let try this :

Go to

~/library/keychains

select all the files and put them in a new folder (just using the default label, New Folder With Items), then log out (under the Apple menu) and then log back in again.

1. Open settings

2. Go in “iCloud”

3. Enter your Apple ID and password

Use the same Apple ID for all your device's

4. Merge your data

The iCloud sync option screen will appear. You will be prompted to either “Merge” or “Don’t Merge”. Merge means that your content (contacts, calendar events, bookmarks, etc) from both your iCloud account and your iOS device will exchange information. For example: if you have one contact on your phone and four contacts on your iCloud account, both iCloud and the phone will end up with the same 5 contacts. If you choose “Don’t Merge”, content from iCloud will replace what you have on your iOS device (using the same example as above, “Don’t Merge” will overwrite the one contact on your phone and you will end up with the four contacts from iCloud and lose the one that was on the phone). It is always recommended to “Merge”. 

5. Set your Location Preference

You will then be prompted to either “OK” or “Don’t Allow” iCloud to use the location of your iOS device. Choosing “OK” will enable the Find My iPhone/iPad feature on the device which allows you to log into any iOS device or computer and locate, lock, remote wipe, and send a message to your iOS device. It is strongly recommended to enable this feature.

6. Be patient

The iCloud Drive syncing takes some time to initiate in the background, if you are using it the first time. 

And if you need help about Handoff, follow the instructions on this page :

macOS Sierra: Pick up where you left off with Handoff - Apple Supporthttps://support.apple.com/kb/PH25169

This Library folder is normally hidden from view, so if you can’t find it :

1. Click on the Finder icon on your Dock
2. Click on the Go menu at the top of the screen and select Home
3. Click on the View menu and select Show View Options.
4. A new window will appear. Insert a checkmark in the box next to Show Library Folder.
5. Your Library folder is made immediately visible within your Home folder.

And then

1. Click on the Finder icon on your Dock
2. Click on the Go menu at the top of the screen and select Go to folder...
3. Enter this " ~/library/keychains "
4. Select all the files and put them in a new folder (just using New Folder with selection, from "File" on the top bar), then log out (under the Apple menu) and then log back in again.